 /*******************************************************************************
  * Copyright (c) 2005 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/epl-v10.html
  *
  * Contributors:
  * IBM Corporation - initial API and implementation
  *******************************************************************************/
 package org.eclipse.ui.internal.texteditor.quickdiff.compare.equivalence;

 /**
  *
  * @since 3.2
  */
 public final class DJBHashFunction implements IHashFunction {

     public Hash computeHash(CharSequence string) {
         return new IntHash(hash(string));
     }
     
     private int hash(CharSequence seq){
         int hash = 5381;
         int len= seq.length();
         for (int i= 0; i < len; i++) {
             char ch= seq.charAt(i);
             hash = ((hash << 5) + hash) + ch; /* hash * 33 + ch */
         }

         return hash;
     }

 }

